Mockito when checking for specific object property value

Question

I have the following in a working test:

when(client.callApi(anyString(), isA(Office.class))).thenReturn(responseOne);

Note that client is a Mock of class Client.

I want to change "isA(Office.class)" to tell it to match where the "id" property of an Office instance is "123L". How can I specify that I want a specific argument value in the method of a mocked object?

Edit: Not a duplicate because I'm trying to use it on a "when" and the linked question (and other resources I've found) are using ArgumentCaptor and ArgumentMatcher on "verify" and "assert". I'm thinking I can't actually do what I'm trying and will try out another way. Of course, I'm willing to be shown otherwise.

Answer 1

Reopening as requested, but the solution (use an ArgumentMatcher) is identical to the one in the linked answer. Naturally, you can't use an ArgumentCaptor when stubbing, but everything else is the same.

class OfficeWithId implements ArgumentMatcher<Office> {
  long id;

  OfficeWithId(long id) {
    this.id = id;
  }

  @Override public boolean matches(Office office) {
    return office.id == id;
  }

  @Override public String toString() {
    return "[Office with id " + id + "]";
  }
}

when(client.callApi(anyString(), argThat(new IsOfficeWithId(123L)))
    .thenReturn(responseOne);

Because ArgumentMatcher has a single method, you can even make it a lambda in Java 8:

when(client.callApi(anyString(), argThat(office -> office.id == 123L))
    .thenReturn(responseOne);

If you're already using Hamcrest, you can adapt a Hamcrest matcher using MockitoHamcrest.argThat, or use the built-in hasPropertyWithValue:

when(client.callApi(
         anyString(),
         MockitoHamcrest.argThat(hasPropertyWithValue("id", 123L))))
    .thenReturn(responseOne);

Answer 2

I ended up going with "eq". This was ok in this case because the objects are pretty simple. First I created an object that is the same as what I expect to get back.

Office officeExpected = new Office();
officeExpected.setId(22L);

Then my 'when' statement becomes:

when(client.callApi(anyString(), eq(officeExpected))).thenReturn(responseOne);

This allows me to have better checking than "isA(Office.class)".